35 lines
544 B
Swift
35 lines
544 B
Swift
struct KPrimeGen: Sequence, IteratorProtocol {
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let k: Int
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private(set) var n: Int
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private func isKPrime() -> Bool {
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var primes = 0
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var f = 2
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var rem = n
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while primes < k && rem > 1 {
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while rem % f == 0 && rem > 1 {
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rem /= f
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primes += 1
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}
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f += 1
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}
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return rem == 1 && primes == k
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}
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mutating func next() -> Int? {
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n += 1
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while !isKPrime() {
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n += 1
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}
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return n
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}
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}
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for k in 1..<6 {
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print("\(k): \(Array(KPrimeGen(k: k, n: 1).lazy.prefix(10)))")
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}
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